Human Evolution: Genes, Genealogies and Phylogenies

Human Evolution: Genes, Genealogies and Phylogenies

Graeme Finlay

Language: English

Pages: 374

ISBN: 1107040124

Format: PDF / Kindle (mobi) / ePub

Controversy over human evolution remains widespread. However, the human genome project and genetic sequencing of many other species have provided myriad precise and unambiguous genetic markers that establish our evolutionary relationships with other mammals. Human Evolution: Genes, Genealogies and Phylogenies identifies and explains these identifiable, rare and complex markers including endogenous retroviruses, genome-modifying transposable elements, gene-disabling mutations, segmental duplications and gene-enabling mutations. The new genetic tools also provide fascinating insights into when and how many features of human biology arose: from aspects of placental structure, vitamin C dependence and trichromatic vision, to tendencies to gout, cardiovascular disease and cancer. Bringing together a decade's worth of research and tying it together to provide an overwhelming argument for the mammalian ancestry of the human species, the book will be of interest to professional scientists and students in both the biological and biomedical sciences.

…GTTTGC… target site sequence, and otherwise neatly spliced into the mouse genome [10]. A unique insertion event in one cell induced an uncontrolled programme of cell division, leading to a proviral copy in each of myriad descendant cells. We can detour from retroviruses briefly. Several other human cancers arise when bits of viral DNA are insinuated into the genomic DNA of infected cells. No other class of oncogenic virus Retroviruses and the monoclonality of ­t umours 31 upstream flanking

mammalian evolution The mammals are divided into three groups. Mammals that are nourished before birth through a placenta connected to their mother’s uterus lining constitute the Eutheria. This term is derived from the Greek terms eu-­(true or well-­formed) and theria (wild animals or beasts). We have placed ourselves, somewhat immodestly, among the real beasts. In addition to these are the marsupials (the Metatheria; or loosely, the other beasts) and egg-­laying monotremes (the Prototheria;

they were generated) into modules Exaptation of ­T Es 117 possessing genetic functionality (that have contributed to the viability of that organism’s descendants). 2.5.1 Raw material for new genes Alu elements have contributed new genes to our genome. A classical example is the BC200 gene (later renamed BCYRN1). This arose from an Alu element that spliced itself into the genome of an ancestor of the apes and monkeys. This Alu element spawned a multitude of daughters (some 200 are scattered

extant species have been located in the genome of Neanderthals. The ages of these pseudogenes have been estimated at 620,000 and nearly 3 million years. At the other end of the temporal scale, numts have been shown to date from early in anthropoid (ape–monkey) history, as instances are shared by humans, OWMs and probably NWMs (Table 3.1) [23]. 144 ­Pseudogenealog Table 3.1. The distribution of numts in primate genomes ­[23] Mitochondrial gene from which the numt was Species possessing derived

more-­or-­less intact, and we have not started to take the wood for any other use.) To be human is to be unable to make certain sugars, to have a defective pelt and to have malformed cheek muscles. About 40 genes have been inactivated specifically in human beings [49]. We have simply lost (and are still losing) some of the capacities shared by our primate relations. ­Pseudogene 157 G to A human chimp gorilla macaque bushbaby tree shrew mouse rat guinea pig rabbit hedgehog dog horse cow